Bulb holders

ABSTRACT

A bulbholder for an electric lamp includes a hollow conductive sleeve which is secured to the lamp reflector, and which is provided with a bulb engaging surface defined by an internal shoulder. The fulcrum part is provided at one end of the sleeve, and at the same end of the sleeve diametrically opposite the fulcrum part there is provided a latch part. The latch part is in the form of a gate terminal and an insulating contact plate carrying resilient contact member is pivotally engaged with the fulcrum part. The plate carrying the contact member can be pivoted to a position wherein the contact member is stressed against the terminal of a bulb and urges the bulb into engagement with the bulb engaging surface of the sleeve, and the plate can be retained in the operative position by a latch member in the form of a connector which engages the latch part defined by the blade terminal.

United States Patent 91 Rathband 1 1 BULB HOLDERS [75] Inventor: Walter Howard vRathbantl,

Burntwood, near Walsall, England 73 Assignee: Butlers Limited, Birmingham,

England 22 Filed: Aug.25, 1971 21 Appl. No.: 174,768

[30] Foreign Application Priority Data Aug. 25, 1970 Great Britain 40,861/70 [52] U.S. Cl 339/75 R, 240/13, 240/153,

[51] Int. Cl... H0lr 13/54, G03b 15/02, F21v 17/00 [58] Field of Search 339/75, 45 T, 91 R, 339/91 L, 119,176 L, 127, 4, 34; 240/13, 2

C,l53, 10.6 R, 10.63; 95/11.5 R

[ June 26, 1973 Primary ExaminerJoseph H. McGlynn Assistant Examiner-William F. Pate, lll Attorney-Holman & Stern [57] ABSTRACT A bulbholder for an electric lamp includes a hollow .conductive sleeve which is secured to the lamp reflector, and which is provided with a bulb engaging surface defined by an internal shoulder. The fulcrum part is provided at one end of the sleeve, and at the same end of the sleeve diametrically opposite the fulcrum part there is provided a latch part. The latch part is in the form of a gate terminal and an insulating contact plate carrying resilient contact member is pivotally engaged with the fulcrum part. The plate carrying the contact member can be pivoted to a position wherein the contact member is stressed against the terminal of a bulb and urges the bulb into engagement with the bulb engaging surface of the sleeve, and the plate can be retained in the operative position by a latch member in the form of a connector which engages the latch part defined by the blade terminal.

6 Claims, 3 Drawing Figures BULB HOLDERS This invention relates to bulbholders for electric lamps.

A bulbholder according to the invention includes a hollow conductive sleeve having an internal bulb engaging surface, a fulcrum part at one end of the sleeve and a latch part also at said one end of the sleeve, the latch part being spaced around the periphery of the said sleeve from the fulcrum part, an insulating contact plate and a resilient contact member carried by said plate, said plate engaging said fulcrum part so that the plate is pivotable about said fulcrum part relative to said sleeve and there being a latch member engageable with said latch part to retain said plate in an operative position relative to the sleeve, said contact member being stressed against a terminal of a bulb in use to urge said bulb into engagement with said bulb engaging surface.

Preferably said fulcrum part includes a tongue integral with said sleeve, said tongue extending through an aperture in said plate.

Conveniently said latch part is an electrical terminal member integral with said sleeve and said plate is formed with an aperture through which the terminal member extends, and said latch member is defined by an electrical connector which mates with said terminal member, the connector when engaged with the terminal member preventing withdrawal of the terminal member through said aperture in the plate.

Preferably the arrangement is such that in use the plate and the latch member interengage in such a manner that the latch member cannot readily be disengaged from the latch part without moving the plate against the action of the resilient contact member to disengage the plate from the latch member.

Desirably the plate carries a pair of resilient contact members engageable with the bulb in use.

Conveniently the latch member, the latch part, and the sleeve form part of the electrical circuit of the bulb in use.

One example of the invention is illustrated in the accompanying drawings wherein FIG. 1 is a sectional view of a lamp utilizing a bulbholder in accordance with one example of the invention,

FIG. 2 is a sectional view of the bulbholder shown in FIG. 1, but taken at a plane of 90 to the plane of the sectional view of FIGJI, and

FIG. 3 is an end view of the arrangement shown in FIG. 2.

Referring to the drawings the lamp includes a dished metal reflector 11 the concave surface of which is silvered to render it highlyreflective. Closing the wider, open end of the reflector 11 is a lens 12 which is trapped in sealing engagement with the reflector 11 by conventional means. At its end remote from the lens 12 the reflector 11 is formed with a central aperture, and secured to the reflector, and extending generally coaxially of the reflector 11 from the aperture, in a direction away from the lens 12 is a bulb holder assembly 13.

The assembly 13 includes a conductive, cylindrical sleeve 14 secured at one end to the periphery of the aperture in the reflector 11, by a rolled portion 15 of the sleeve 14. The rolled portion of the sleeve 14 defines an internal shoulder 16 within the sleeve 14 the shoulder l6 constituting a bulb engaging surface. Abutting against the bulb engaging surface 16 in use is the conductive disc 17 of the cap 18 of a bulb. The disc 17 is provided intermediate the ends of the cap 18, and the remainder of the cap 18 remote from the envelope of the bulb extends in a direction away from the lens 12, and projects from the free end of the sleeve 14. At its free end the sleeve 14 is formed with an integral tongue 19 which extends radially outwardly from the sleeve 14. Diametrically opposite the tongue 19 the sleeve 14 is formed with an integral blade connector 21 which also extends radially outwardly from the sleeve 14.

The bulbholder assembly 13 further includes an insulating contact plate 22. The contact plate 22 is formed with a centrally disposed aperture 23 through which the cap 18 of the bulb projects in use. The plate 22 is formed with a slot 24 through which the tongue 19 extends, the tongue 19 constituting a fulcrum about which the plate 22 can be pivoted relative to the sleeve 14. Diametrically opposite the slots 24 the plates 22 is formed with a rectangular aperture 25 through which the blade terminal 21 projects when the plates 22 is pivoted to a position transverse to the axis of the sleeve 14.

Riveted to the plate 22 are a pair of phosphor bronze spring contact blades 26,27, the blades 26,27 being aligned on a diameter of the aperture 23 of the plate 22, and being secured to the plate 22 on opposite sides of the aperture. The inner ends of the blades 26,27 terminate adjacent the center of the aperture 23 in the. plate 22, and at their outer ends the blades 26,27 define respective socket connectors for the reception of terminal pins secured to respective conductive leads.

In use, the bulb of the lamp is a twin filament bulb, and the bulb is engaged with the assembly 13 with the disc 17 of the bulb engaging the surface 16 of the sleeve 14. The sleeve 14 includes an internal axially extending rib not shown which engages a corresponding recess formed in the disc 17 to ensure that the bulb is orientated in a desired manner with respect to the bulbholder assembly 13. When the plate 22 is moved to said position transverse to the axis of the sleeve 14 the blades 26,27 engage respective filament terminals at the axial and of the cap 18 of the bulb. The two filaments of the bulb of course have a common connection to the cap 18, and so one end of each of the filaments is electrically connected through the cap 18 of the disc 17, and the sleeve 14 to the terminal blade 21. The other end of the first of the filaments is electrically connected to the blade 27, while the other end of the second filament is electrically connected to the blade 26. Electrical connections to the blades 26,27 aremade by way of conductive leads carrying terminal pins which engage in the socket connectors of the blades 26,27 respectively, and the electrical connections to the terminal blade 21 is made by way of a socket connector 28 electrically connected to a respective lead. The socket connector 28 is not shown in FIG. 2. The socket connector 28 is engaged with the blade 21 when the plate 22 has been moved to said position transversed to the axis of the sleeve 14. Thus the blade 21 projects from the surface of the plate 22 remote from the sleeve 14, and the aperture 25 in the plate 22 is such that when the connector 28 is engaged with the terminal 21, then the connector 28 prevents withdrawal of the terminal 21 through the aperture 25. Thus the connector 28 locks the plate 22 in said position transverse to the axis of the sleeve 14. The arrangement is such that when the plates 22 is in said position then the blades 26,27 are stressed, so that the bulb is held firmly in position in the bulbholder, and the plate 22 bears against the connector 28. The arrangement of the connector 28 and the aperture 25 is such that when the plates 22 is urged against the connector 28 then the plate 22 and the connector 28 become engaged in such a manner that the connector 28 cannot be readily disengaged from the terminal 21. In order to disengage the connector 28 from the terminal 21 to permit removal of the bulb, the plate 22 must be moved about the fulcrum constituted by the tongue 19 in a direction towards the reflector 11, against the action of the blades 26, 27, to disengage the plate 22 from the connector 28. The connector 28 can then be disengaged from the terminal 21 thereby permitting the plate 22 to be pivoted about the tongue 19 to permit withdrawal of the bulb from the bulbholder.

Where the bulb is of the single filament type, then both blades 26, 27 engage a single terminal on the cap of bulb and an electrical connection is made to one of the blades 26, 27 the remaining blade constituting resilient means, but not constituting part of the electrical circuit. If desired, a single blade could be used in such an arrangement, but it will be appreciated that it is convenient to provide a pair of blades, so that a common unit can be used with either single filament or double filament bulbs.

It will be appreciated that the sleeve 14 could be secured to the reflector 1 1 by any convenient means, and could if desired, be integral with the reflector 11.

I claim:

1. A bulb holder for electric lamps including a hollow conductive sleeve having an internal bulb engaging surface, a fulcrum part at one end of the sleeve and a latch part also at said one end of the sleeve, the latch part being spaced around the periphery of the said sleeve from the fulcrum part, an insulating contact plate and a resilient contact member carried by said plate, said plate engaging said fulcrum part so that the plate is pivotable about said fulcrum part relative to said sleeve and there being a latch member engageable with said latch part to retain said plate in an operative position relative to the sleeve, said contact member being stressed against a terminal of a bulb in use to urge said bulb into engagement with said bulb engaging surface.

2. A bulb holder as claimed in claim 1 in which said fulcrum part includes a tongue integral with said sleeve, said tongue extending through an aperture in said plate.

3. A bulb holder as claimed in claim 1 in which said latch part is an electrical terminal member integral with said sleeve, and said plate is formed with an aperture through which the terminal member extends, the latch member being defined by an electrical connector which mates with said terminal member and the connector when engaged with the terminal member preventing withdrawal of the terminal member through said aperture in the plate.

4. A bulb holder as claimed in claim 1 in which the plate and the latch member interengage in such a manner that the latch member cannot readily be disengaged from the latch part without moving the plate against the action of the resilient contact member to disengage the plate from the latch member.

5. A bulb holder as claimed in claim 1 in which the plate carries a pair of resilient contact members engageable with the bulb in use.

6. A bulb holder as claimed in claim 1 in which the latch member the latch part, and the sleeve form part of the electrical circuit of the bulb in use.

t l k k 

1. A bulb holder for electric lamps including a hollow conductive sleeve having an internal bulb engaging surface, a fulcrum part at one end of the sleeve and a latch part also at said one end of the sleeve, the latch part being spaced around the periphery of the said sleeve from the fulcrum part, an insulating contact plate and a resilient contact member carried by said plate, said plate engaging said fulcrum part so that the plate is pivotable about said fulcrum part relative to said sleeve and there being a latch member engageable with said latch part to retain said plate in an operative position relative to the sleeve, said contact member being stressed against a terminal of a bulb in use to urge said bulb into engagement with said bulb engaging surface.
 2. A bulb holder as claimed in claim 1 in which said fulcrum part includes a tongue integral with said sleeve, said tongue extending through an aperture in said plate.
 3. A bulb holder as claimed in claim 1 in which said latch part is an electrical terminal member integral with said sleeve, and said plate is formed with an aperture through which the terminal member extends, the latch member being defined by an electrical connector which mates with said terminal member and the connector when engaged with the terminal member preventing withdrawal of the terminal member through said aperture in the plate.
 4. A bulb holder as claimed in claim 1 in which the plate and the latch member interengage in such a manner that the latch member cannot readily be disengaged from the latch part without moving the plate against the action of the resilient contact member to disengage the plate from the latch member.
 5. A bulb holder as claimed in claim 1 in which the plate carries a pair of resilient contact members engageable with the bulb in use.
 6. A bulb holder as claimed in claim 1 in which the latch member, the latch part, and the sleeve form part of the electrical circuit of the bulb in use. 